Question: $ { {-5} \times \left[\begin{array}{rrr}{3} & {-1} & {0} \\ {3} & {4} & {2}\end{array}\right] = {?} } $
Answer: To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{rrr}{-5}\times{3} & {-5}\times{-1} & {-5}\times{0} \\ {-5}\times{3} & {-5}\times{4} & {-5}\times{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{-15} & {5} & {0} \\ {-15} & {-20} & {-10}\end{array}\right]}$